The purpose of the Tissue and Acquisition Core (TAAC) of this YSDRCC proposal is to stimulate and facilitate cutaneous research by providing highly efficient and cost-effective services, facilities, and expert assistance in the acquisition and analysis of samples of normal and diseased skin. The TAAC will facilitate the preparation and analysis of tissue sections derived from experimental tissues provided by investigators, or from archival tissue accessible to the TAAC facility. Sample sources in hand consist of an over 200,000 biopsy specimen archive of diseased skin and serum samples that were submitted to the Yale Dermatopathology Service, and which are cross- referenced by diagnosis in a relational database. Tissue sections and nucleic acids extracted from multiple cases of common and rare diseases can be provided to researchers from this tissue bank (after specific Human Investigation Committee approval is obtained by each interested investigator).